Stromatoporoid sponges were very abundant during the middle Palaeozoic Era and are thought to disappear at the end of th......

目的:建立用高效液相色谱法测定藿香中胡薄荷酮含量的方法。方法:以甲醇-0.2%乙酸铵溶液(70∶30)为流动相,Thermo BDS HYPERSIL C1......

为探究吕家坨井田地质构造格局,根据钻孔勘探资料,采用分形理论和趋势面分析方法,研究了井田7......